100% het - what does it mean?

[DaveyB]

I'm a little puzzled as to what this means. Sometimes you see 100% albino and another time it might be 100% het albino. What's the difference when het is added? Is there no difference and it's just because people can't be bothered to say het?

How are the percentages worked out?
If you have a 100% albino royal and breed it with a normal royal. Would that make it 50% albino or what?

[rob-stl-07]

het means not displaying but carrying the gene. it means that when you breed a het animal the % is how much chance there is of babies of the het being produced.


of course theres alot more detail thats jyst a little bit.
someone correct me if im wrong.

[Athravan]

Het means heterozygous. For a visual animal, two alleles of the gene must be present. Ie. an albino contains albino and albino allelles, allowing a visual albino animal. If only one allelle is present, ie a royal contains albino and normal allelles, normal is the dominant allele - the snake will look normal in every way, but it will be carrying albino.

If you then breed that normal "het" albino, with an albino, you will get some offspring that inherit albino from both parents, and some will be albino - some will be normal het albino.

If you bred a normal with a normal het albino, some of the babies would be het albino, some wouldn't, but you would have no way of telling which of the babies were het, and which weren't, so you would label it 50% het albino. This doesn't mean it carries 50% albino genes, it means it has a 50% chance of being either het albino, or not het albino.

[Ssthisto]

Het doesn't mean "carries but doesn't show a recessive".
It means only and exclusively "The two genes of a pair are different".

A pastel royal python is het for the co/incomplete dominant Pastel gene (a homozygous one is a "Super Pastel").
A spider royal python is probably het for the dominant Spider gene (nobody's ever proven a homozygous one, however)

The percentage shown next to "het" actually reflects how much of a chance THAT animal has of being a carrier for the gene.

A 100% het-for-recessive has either:
One visual recessive parent (The parent HAD to give the recessive trait to its offspring)
One visual recessive offspring (Proving that the "possible" het is a definite one)

They do not produce 100% guaranteed heterozygous offspring - as below:

A 66% het-for-recessive has a 2-in-3 chance of carrying the trait. It has:
2 100% het parents

A 50% het-for-recessive has a 1-in-2 chance of carrying the trait. It has:
1 100% het parent

Anything lower than 50% is a "possible het from a possible het" and should really be treated as a normal.

[pied pythons]

nice post Ssthisto...

It is so frequently thought that heterozygous or 'het' only applies to reccessive morphs...

Where in fact it only means that the alleles in question are different...

I think the easiest way to consider it is this:

A HOMOsexual relationship consists of two people of the SAME sex...
A HETerosexual relationship consists of two people of DIFFERENT sexes...

Therefore hetero means different

It's sometimes just easier to remember when you're starting out with genetics etc...

[DaveyB]

I think I'm understanding a bit better from some of the answers. What about if I had a
Pinstripe Royal - not sure about what genes it has but it looks like a pinstripe
Normal Royal - just plain jane
(I don't own these snakes, it's just an example.)

If there were two normal looking hatchlings and 2 pinstripe looking ones. What would you have?
The normal looking ones would be 50% het pinstripe?
The pinstripe looking ones would be???

[GazEmm]

Originally Posted by DaveyB

I think I'm understanding a bit better from some of the answers. What about if I had a
Pinstripe Royal - not sure about what genes it has but it looks like a pinstripe
Normal Royal - just plain jane
(I don't own these snakes, it's just an example.)

If there were two normal looking hatchlings and 2 pinstripe looking ones. What would you have?
The normal looking ones would be 50% het pinstripe?
The pinstripe looking ones would be???

A pinstripe works a little different to albinos and the other recessive traits.

Basically, for your example a pinstripe x normal will give you 50% chance (i think) of each egg being a pinstripe and obviously leaving a 50% chance of getting a normal.

Any normal babies will be just that, completely normal. Again the same with the pinstripe...any pinstripes that hatch are simply pinstripe royals.

There are no % of het's with pinstripes as there are with albinos, pieds etc.

Pop to the genetic section though, some really useful threads on there to get you going

[Ssthisto]

Originally Posted by DaveyB

I think I'm understanding a bit better from some of the answers. What about if I had a
Pinstripe Royal - not sure about what genes it has but it looks like a pinstripe
Normal Royal - just plain jane
(I don't own these snakes, it's just an example.)

If there were two normal looking hatchlings and 2 pinstripe looking ones. What would you have?
The normal looking ones would be 50% het pinstripe?
The pinstripe looking ones would be???

Ok, Pinstripe appears to be a DOMINANT gene. Therefore, it only takes one copy ("het") to produce a visual Pinstripe - and a homozygous pinstripe looks exactly like a het.

If you produce two normals and two pinstripes, you know your Pinstripe parent is HET for the Pinstripe gene (otherwise it would have produced ALL pinstripes).

The Pinstripe babies are also HET for pinstripe (because they had one normal parent that did not have Pinstripe to give).

The Normal babies are not het for pinstripe at all (or else they'd look like pinstripes).

And if you bred a Pinstripe to a Pinstripe, all of the PINSTRIPE babies are "66% het Pinstripes" - because there's a 1-in-3 chance that they're actually HOMOZYGOUS pinstripe.

[DaveyB]

There's rather a lot to it all then and not as simple as I thought it may be. Would it be fair to say then, that people may not have what snake they think? As you could have bought it from someone who doesn't really understand the genetics

[Athravan]

If you're buying a snake that comes with a "het" that isn't visual, you should really ask what the parents were, if you can see them, and if it was bred by a reliable breeder - if there is any paperwork to come with it.

It is very easy for mistakes to be made with hets, or even worse, for deliberate lies to be told in order to increase the price of snakes. Always buy from a trusted source with good reputation if spending extra money on any hidden genetics.